Corythion aerophila (Decloitre, 1964)
Basionym: Corythion dubium var. aerophila Decloitre, 1950

Diagnosis: This variety is distinguished from the type by a large visor preceding the pseudostome, much larger than in the type and featuring several rows of scales. Finally, this visor, forming a peristomial region, appears to be added to the theca and is connected to it by a strong constriction. The posterior edge of the pseudostome is straight or even convex. The pseudostome is bordered by very fine small beads that are difficult to see except under phase contrast. The plates of the theca are very small, arranged without order, except for those bordering the theca laterally. When a theca breaks, the visor detaches as a block from the rest of the theca. Only once have we observed a broken theca with a fragment of the visor still attached to the rest of the theca. The ventral part is almost flat, while the dorsal part is regularly rounded.

Dimensions: Shell length 50—57 µm; width 30—35 µm.

Ecology:

Remarks: